I have a 4 disk SATA III controller with four 4 TB drives. I created a 4 disk parity storage pool with a single Virtual disk. One of the drives completely died and is no longer visible to windows. I replace the drive with new disk. I added the new drive to the Storage pool and attempted to repair the degraded virtual disk. When I right click on the virtual disk and select "Repair Virtual disk" the status shows its repairing and withing 5 seconds it will display "repair 100%", but the virtual disk stays in a degraded state.
I have also tried to remove the failed drive that still shows up under physical Disks, but the system will not allow me to remove it.